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Dirt Bike Engine

Dirt Bike Engine

Dirt Bike Engine

Dirt Bike Engine Parts at JJ Motorsports

Discover a full range of dirt bike engine components for rebuilding or upgrading your performance from JJ Motorsports. From crankshafts to cylinder heads and piston kits, these precision-engineered components ensure reliable performance. For additional upgrades, check out our full selection of off-road dirt bike parts to keep your engine running at peak efficiency on the track or trails.

Shop trusted brands like Wiseco for forged piston kits and K&N for high-flow oil filters. Explore related categories such as Dirt Bike Air and Fuel for intake upgrades or Dirt Bike Exhaust for complete systems.

Browse our in-stock inventory below with same-day shipping and expert support. Questions? Contact us for fitment advice!

  • Product
  • Qty in Cart
  • Quantity
  • Price
  • Subtotal
  • MOOSE RACING Complete Motor Gasket Kit - CR85R 808211

    MOOSE RACING Complete Motor Gasket Kit - CR85R 808211

    MOOSE RACING

    $58.40
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost., High-tech materials provide unmatched reliability and performance, Rebuild the engine and transmission with total confidence as each set is designed for durability and...
    09340265
    SKU:
    09340265
    Availability:
    Ships Same Business Day
    Weight:
    0.16 LBS
    TYPE:
    ENGINE
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    PRODUCT NAME:
    GASKET
    UNITS:
    KIT
    $58.40
    Qty in Cart: 0
    Quantity:
    Price:
    $58.40
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - YZ/WR400 811675

    MOOSE RACING Motor Gasket Kit with Seal - YZ/WR400 811675

    MOOSE RACING

    $140.18
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost, Rebuild the engine and transmission with total confidence as each set is designed for durability and accurate fit, Oil seals are genuine OEM replacement seals, Sets include...
    09341486
    SKU:
    09341486
    Availability:
    Ships Same Business Day
    Weight:
    0.40 LBS
    TYPE:
    ENGINE
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    PRODUCT NAME:
    GASKET
    UNITS:
    KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $140.18
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - Husqvarna/KTM 811365

    MOOSE RACING Motor Gasket Kit with Seal - Husqvarna/KTM 811365

    MOOSE RACING

    $174.50
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost, Rebuild the engine and transmission with total confidence as each set is designed for durability and accurate fit, Oil seals are genuine OEM replacement seals, Sets include...
    09344789
    SKU:
    09344789
    Availability:
    Ships Same Business Day
    Weight:
    0.50 LBS
    PRODUCT NAME:
    GASKET
    TYPE:
    ENGINE
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    UNITS:
    KIT
    Qty in Cart: 0
    Quantity:
    Price:
    $174.50
    Subtotal:
  • MOOSE RACING Complete Motor Gasket Kit - KDX200 808440

    MOOSE RACING Complete Motor Gasket Kit - KDX200 808440

    MOOSE RACING

    $73.01
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost., High-tech materials provide unmatched reliability and performance, Rebuild the engine and transmission with total confidence as each set is designed for durability and...
    M808440
    SKU:
    M808440
    Availability:
    Ships Same Business Day
    Weight:
    0.16 LBS
    TYPE:
    ENGINE
    PRODUCT NAME:
    GASKET
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    UNITS:
    KIT
    TYPE:
    COMPLETE
    Qty in Cart: 0
    Quantity:
    Price:
    $73.01
    Subtotal:
  • MOOSE RACING Complete Motor Gasket Kit - RM250 808593

    MOOSE RACING Complete Motor Gasket Kit - RM250 808593

    MOOSE RACING

    $112.43
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost., High-tech materials provide unmatched reliability and performance, Rebuild the engine and transmission with total confidence as each set is designed for durability and...
    09340974
    SKU:
    09340974
    Availability:
    Ships Same Business Day
    Weight:
    0.21 LBS
    PRODUCT NAME:
    GASKET
    UNITS:
    KIT
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    TYPE:
    ENGINE
    Qty in Cart: 0
    Quantity:
    Price:
    $112.43
    Subtotal:
  • POWERSTANDS RACING Case Saver/Sprocket Cover - Blue 07-04150-25

    POWERSTANDS RACING Case Saver/Sprocket Cover - Blue 07-04150-25

    POWERSTANDS RACING

    $99.95
    Tough protection against broken chain from cracking engine cases, Machined lightweight design, Look so much better than stock cover, Replace OEM plastic sprocket cover, Anodized finish
    09500788
    SKU:
    09500788
    Availability:
    Ships Same Business Day
    Weight:
    0.85 LBS
    PRODUCT NAME:
    CASE SAVER
    PRODUCT NAME:
    SPROCKET COVER
    TYPE:
    ENGINE
    COLOR/FINISH:
    BLUE
    RIDING STYLE:
    STREET
    UNITS:
    EACH
    COLOR/FINISH:
    ANODIZED
    RIDING STYLE:
    OFF-ROAD
    $99.95
    Qty in Cart: 0
    Quantity:
    Price:
    $99.95
    Subtotal:
  • POWERSTANDS RACING Drain Plug 00-01946-24

    POWERSTANDS RACING Drain Plug 00-01946-24

    POWERSTANDS RACING

    $25.95
    Bolts are CNC machined from high-quality aluminum, Embedded magnet helps keep bolt in place, Predrilled holes make for easy installation of safety wires
    09200108
    SKU:
    09200108
    Availability:
    Ships Same Business Day
    Weight:
    0.21 LBS
    COLOR/FINISH:
    RED
    MATERIAL:
    ALUMINUM
    RIDING STYLE:
    STREET
    RIDING STYLE:
    UTV
    FEATURES:
    MAGNETIC
    PRODUCT NAME:
    BOLT
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    OIL DRAIN
    DIAMETER - THREAD SIZE METRIC:
    M12 X 1.50 X 15 MM
    RIDING STYLE:
    ATV
    UNITS:
    EACH
    Qty in Cart: 0
    Quantity:
    Price:
    $25.95
    Subtotal:
  • Pro Circuit Water Pump Cover with Impeller for Honda CRF450R 2019 WPH09450

    Pro Circuit Water Pump Cover with Impeller for Honda CRF450R 2019 WPH09450

    PRO CIRCUIT

    $239.95
    Upgrade your Honda's performance with the PRO CIRCUIT Water Pump Cover, expertly crafted from CNC-machined billet aluminum. This cover not only enhances durability but also optimizes water flow, ensuring your engine runs cooler and more efficiently...
    09401180
    SKU:
    09401180
    Availability:
    Ships Same Business Day
    Weight:
    0.36 LBS
    COLOR/FINISH:
    ANODIZED
    MATERIAL:
    BILLET ALUMINUM
    PRODUCT NAME:
    COVER
    RIDING STYLE:
    OFF-ROAD
    COLOR/FINISH:
    MACHINED
    TYPE:
    WATER PUMP
    UNITS:
    SET
    Qty in Cart: 0
    Quantity:
    Price:
    $239.95
    Subtotal:
  • Pro Circuit Water Pump Cover with Impeller for 2004-2006 Suzuki RM-Z250 WPK04250

    Pro Circuit Water Pump Cover with Impeller for 2004-2006 Suzuki RM-Z250 WPK04250

    PRO CIRCUIT

    $239.95
    Enhance your engine's cooling efficiency with the PRO CIRCUIT Water Pump Cover, expertly crafted from CNC-machined billet aluminum. This robust yet lightweight design ensures exceptional durability, delivering superior protection and performance for your...
    09400464
    SKU:
    09400464
    Availability:
    Ships Same Business Day
    Weight:
    0.55 LBS
    COLOR/FINISH:
    ANODIZED
    MATERIAL:
    BILLET ALUMINUM
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    COVER
    TYPE:
    WATER PUMP
    COLOR/FINISH:
    MACHINED
    UNITS:
    SET
    Qty in Cart: 0
    Quantity:
    Price:
    $239.95
    Subtotal:
  • MOOSE RACING Countershaft Sprocket Seal Kit  - KTM 25-4001

    MOOSE RACING Countershaft Sprocket Seal Kit - KTM 25-4001

    MOOSE RACING

    $27.95
    Kits include hardened steel bushing, an upgraded seal, an O-ring (where applicable) and a snap ring or lock washer (where applicable), Made in the U.S.A.
    09350428
    SKU:
    09350428
    Availability:
    Ships Same Business Day
    Weight:
    0.14 LBS
    PRODUCT NAME:
    SEAL KIT
    UNITS:
    KIT
    APPLICATION:
    COUNTERSHAFT
    RIDING STYLE:
    STREET
    RIDING STYLE:
    OFF-ROAD
    $27.95
    Qty in Cart: 0
    Quantity:
    Price:
    $27.95
    Subtotal:
  • MOOSE RACING Countershaft Sprocket Seal Kit  - KTM 25-4003

    MOOSE RACING Countershaft Sprocket Seal Kit - KTM 25-4003

    MOOSE RACING

    $25.95
    Kits include hardened steel bushing, an upgraded seal, an O-ring (where applicable) and a snap ring or lock washer (where applicable), Made in the U.S.A.
    09350430
    SKU:
    09350430
    Availability:
    Ships Same Business Day
    Weight:
    0.16 LBS
    RIDING STYLE:
    STREET
    PRODUCT NAME:
    SEAL KIT
    APPLICATION:
    COUNTERSHAFT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $25.95
    Qty in Cart: 0
    Quantity:
    Price:
    $25.95
    Subtotal:
  • MOOSE RACING Countershaft Sprocket Seal Kit  - KTM 25-4006

    MOOSE RACING Countershaft Sprocket Seal Kit - KTM 25-4006

    MOOSE RACING

    $23.95
    Kits include hardened steel bushing, an upgraded seal, an O-ring (where applicable) and a snap ring or lock washer (where applicable), Made in the U.S.A.
    09350433
    SKU:
    09350433
    Availability:
    Ships Same Business Day
    Weight:
    0.10 LBS
    APPLICATION:
    COUNTERSHAFT
    PRODUCT NAME:
    SEAL KIT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    $23.95
    Qty in Cart: 0
    Quantity:
    Price:
    $23.95
    Subtotal:
  • MOOSE RACING Countershaft Sprocket Seal Kit - Yamaha 25-4023

    MOOSE RACING Countershaft Sprocket Seal Kit - Yamaha 25-4023

    MOOSE RACING

    $22.95
    Kits include hardened steel bushing, an upgraded seal, an O-ring (where applicable) and a snap ring or lock washer (where applicable), Made in the U.S.A.
    09350448
    SKU:
    09350448
    Availability:
    Ships Same Business Day
    Weight:
    0.13 LBS
    APPLICATION:
    COUNTERSHAFT
    RIDING STYLE:
    OFF-ROAD
    UNITS:
    KIT
    PRODUCT NAME:
    SEAL KIT
    $22.95
    Qty in Cart: 0
    Quantity:
    Price:
    $22.95
    Subtotal:
  • MOOSE RACING Motor Gasket Kit with Seal - KTM 811371

    MOOSE RACING Motor Gasket Kit with Seal - KTM 811371

    MOOSE RACING

    $105.55
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost, Rebuild the engine and transmission with total confidence as each set is designed for durability and accurate fit, Oil seals are genuine OEM replacement seals, Sets include...
    09345367
    SKU:
    09345367
    Availability:
    Ships Same Business Day
    Weight:
    0.36 LBS
    RIDING STYLE:
    OFF-ROAD
    TYPE:
    COMPLETE
    UNITS:
    KIT
    PRODUCT NAME:
    GASKET
    TYPE:
    ENGINE
    $105.55
    Qty in Cart: 0
    Quantity:
    Price:
    $105.55
    Subtotal:
  • MOOSE RACING Valve Shim - 8.90 x 2.28 - 5 pack MSE5PK890228

    MOOSE RACING Valve Shim - 8.90 x 2.28 - 5 pack MSE5PK890228

    MOOSE RACING

    $10.95
    Complete valve shim kits make it easier to maintain your valve train, Forged from 4140 cold rolled steel, not sintered, Laser-etched size on each shim for identification, A great addition to any mechanic's tool box, Refills sold to dealers in 5-packs;...
    09261919
    SKU:
    09261919
    Availability:
    Ships Same Business Day
    Weight:
    0.02 LBS
    OUTSIDE DIAMETER METRIC:
    8.90 MM
    RIDING STYLE:
    ATV
    TYPE:
    VALVE
    VALVE SHIM THICKNESS METRIC:
    2.28 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    STREET
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    UNITS:
    5 PACK
    MATERIAL:
    ROLLED
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    RIDING STYLE:
    SNOW
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Valve Shim - 8.90 x 2.48 - 5 pack MSE5PK890248

    MOOSE RACING Valve Shim - 8.90 x 2.48 - 5 pack MSE5PK890248

    MOOSE RACING

    $10.95
    Complete valve shim kits make it easier to maintain your valve train, Forged from 4140 cold rolled steel, not sintered, Laser-etched size on each shim for identification, A great addition to any mechanic's tool box, Refills sold to dealers in 5-packs;...
    09261924
    SKU:
    09261924
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    VALVE SHIM THICKNESS METRIC:
    2.48 MM
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    RIDING STYLE:
    ATV
    RIDING STYLE:
    STREET
    MATERIAL:
    ROLLED
    MATERIAL:
    STEEL
    RIDING STYLE:
    OFF-ROAD
    OUTSIDE DIAMETER METRIC:
    8.90 MM
    PRODUCT NAME:
    SHIM
    RIDING STYLE:
    SNOW
    RIDING STYLE:
    UTV
    RIDING STYLE:
    WATERCRAFT
    TYPE:
    VALVE
    UNITS:
    5 PACK
    Qty in Cart: 0
    Quantity:
    Price:
    $10.95
    Subtotal:
  • MOOSE RACING Head Cover Gasket - Yamaha 817944

    MOOSE RACING Head Cover Gasket - Yamaha 817944

    MOOSE RACING

    $26.58
    Moose can now handle all your gasket and seal needs at a fraction of OEM cost, High-tech materials provide unmatched reliability and performance, Rebuild the engine and transmission with total confidence as each set is designed for durability and...
    09346181
    SKU:
    09346181
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    PRODUCT NAME:
    GASKET
    ENGINE TYPE:
    4-STROKE
    TYPE:
    VALVE COVER
    UNITS:
    EACH
    MATERIAL:
    RUBBER
    RIDING STYLE:
    OFF-ROAD
    $26.58
    Qty in Cart: 0
    Quantity:
    Price:
    $26.58
    Subtotal:
  • MOOSE RACING Ignition Cover Gasket 816177

    MOOSE RACING Ignition Cover Gasket 816177

    MOOSE RACING

    $11.14
    Made in the U.S.A.
    09346934
    SKU:
    09346934
    Availability:
    Ships Same Business Day
    Weight:
    0.07 LBS
    TYPE:
    IGNITION COVER
    RIDING STYLE:
    OFF-ROAD
    PRODUCT NAME:
    GASKET
    UNITS:
    EACH
    $11.14
    Qty in Cart: 0
    Quantity:
    Price:
    $11.14
    Subtotal:
  • MOOSE RACING Cam Chain 250-8136

    MOOSE RACING Cam Chain 250-8136

    MOOSE RACING

    $4.95
    Made from the highest-quality select steel alloys, Lightweight and great durability, Feature precision solid bushings and shot-peened, providing maximum strength, Made to meet or exceed OEM standards
    09250819
    SKU:
    09250819
    Availability:
    Ships Same Business Day
    Weight:
    0.65 LBS
    RIDING STYLE:
    OFF-ROAD
    BASE FINISH:
    RAW
    CHAIN SIZE:
    82RH2015
    COLOR/FINISH:
    RAW
    RIDING STYLE:
    ADVENTURE TOURING / DUAL-SPORT
    UNITS:
    EACH
    MATERIAL:
    STEEL
    MODEL:
    SILENT
    PRODUCT NAME:
    CHAIN
    TYPE:
    CAM
    Qty in Cart: 0
    Quantity:
    Price:
    $4.95
    Subtotal:
  • MOOSE RACING Case Saver Guard - CRF150 CSG12

    MOOSE RACING Case Saver Guard - CRF150 CSG12

    MOOSE RACING

    $37.95
    Made out of a highly durable, high-temperature, impact-resistant nylon, Offers you the protection you're looking for like no other, This slim design eliminates the bulky stock cover feel and offers more protection as well, Come in black with anodized red...
    09500375
    SKU:
    09500375
    Availability:
    Ships Same Business Day
    Weight:
    0.15 LBS
    COLOR/FINISH:
    BLACK
    RIDING STYLE:
    OFF-ROAD
    COLOR/FINISH:
    RED
    TYPE:
    CASE SAVER
    MATERIAL:
    NYLON
    PRODUCT NAME:
    GUARD
    UNITS:
    EACH
    Qty in Cart: 0
    Quantity:
    Price:
    $37.95
    Subtotal:
  • Total: items /

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Dirt Bike Engine Parts

Keep your dirt bike running smoothly and prolong the life of its engine with essential general maintenance. But when parts start to break down, don't let it stop you from getting out on the trails! JJ Motorsports has all that you need for minor jobs like oil changes or major overhauls such as a complete rebuild - carrying top aftermarket brands . Get back in gear faster by shopping our full line of high-quality dirt bike engine parts here today at JJ Motorsports!

 

At JJ Motorsports, we want to make sure you don't miss out on the ride! If your motor has blown or radiator smashed, our gearheads can help get you back in the seat. We carry piston kits from top brands like Wiseco and Wrench Rabbit engine kits so that riders have access to a wide range of parts for their dirt bike engine rebuilds. Plus – with gaskets at-the-ready when it comes time for any leakages - no need to worry about maintenance issues either; simply stay up on oil & filter changes and let us take care of everything else. Got queries? Just give one of our knowledgeable staff members a call at 1-231‐767‐5055 where they'll be more than happy provide advice, instructions and tailored answers catered just for YOU!

Big Power, Nice Sound!

Picked up a Pro Circuit pipe and silencer for my YZ125 it’s a game changer. The power feels way better and the sound is awesome.

Tyler D. - 06/12

Perfect Fit

First time ordering here and dang y’all knocked it outta the park! The wheels fit my Ranger UTV perfect, and I’ll definitely be back for more 5 stars all day!

Sarah L. - 08/24

Fast Shipping!!

Ordered on a Monday, and it was on my doorstep by Wednesday! Super impressed with how fast the shipping was.

Jason P. - 09/13

Helps keep cool, works great!

Bought the dual pass Allstar radiator for my build, and it’s been solid. Keeps the engine running cool even on the hottest days no complaints here!

Jake M. - 05/21

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